I've never used a headset in games before, but I've been playing a lot of left 4 dead and just brought arma II and mic would be really useful. ATM I use my digital Z-5500s with a creative X-FI, but the X-FI uses a flexi jack so I can't use a mic and digital out at the same time. Hence the headphones.

I have no idea which one though. I've read a few reviews but can't really decide on how much I need to spend. Are 5.1 headphones a gimmick?

I want decent sound quality, a mic for online games and fairly good build quality. They also need to work on Vista 64bit.

These are the ones I've looked at so far. But any advice on other models would be greatly appreciated!

I have tried a whole heap of headphones but have finally settled with the logitech G35 which is a 7.1 surround and does not need to use a sound card. It has its own drivers and plus into a the USB port.

I've been using Turtle Beach HPA2's for a long time, sound damn great, have an in-line amp, good mic, good 5.1, good bass, good mids, good hi's, good for gaming, music and movies, they're also good for those that wear glasses too apperently because my fiance has decided they're hers now...leaving me with my older and much cheaper plantronics headset.

I'm actually considering getting a set of JVC HA RX900 headphones, and either snagging a Zalman zmc1 clip-on-cable mic or modding the JVC's to accept the mic boom from the HPA2's (it's got a 3.5mm jack and then about 6" of flex and then the foam covered mic). I love the TB's, but I wanted to try something different this time around, if it doesn't work out, the JVC's have tons of padding and she'll probably like em. Another user here by the name of bumblebee, also highly recommends the Cyber Snipa 5.1 headset, which looks great, has 5.1, runs through USB (where'as the HPA2's only use USB for amp power, and then they use standard 3.5 jacks for sound connections, which works great with onboard and x-fi's that I've tested). There's also the Razer Megalodon 7.1 coming out soon (June 30th), a lot of hype, good looks, and uses 4 speakers per cup like the HPA2's and Cyber Snipa's for 5.1 but can also use them to emulate 7.1 better. IIRC the logitechs have just one speaker per cup, so it's a lot more challenging to get 7.1 emulation...but none-the-less the G35's are nice, but to me not worth the money.

I almost snagged a set of Sennheiser PC-350's, but again, the price didn't justify what I felt I would get. Another reason I wanted to go with headphones and add/mod a mic is getting more sound for my buck...and something that will hopefully match or beat my amazing HPA2's without breaking the bank.